Inside Derek & Julianne's Dancing Rehearsal

With seven mirror ball trophies between them, Derek and Julianne Hough are perhaps the most popular dancers on television -- a title that's hard earned, as we found out watching the siblings rehearse.

Julianne explained their philosophy, saying, "We want it to be fun a celebration every night. It shouldn't feel like hard work even though it's going to be."

The brother-sister duo is prepping for their 42-date Move Live Tour, launching May 25 from Utah.

"The reason we're doing the tour right now is that we asked each other what we loved to do," said Derek. "[We're] going back to the basics of performing, and performing in front of a live audience is the best thing we love. There's nothing quite like that."

Watch the video for some cute home videos dating back to their childhood.